Batman is standing on a cliff 120 m high. He is testing a new bat grappling hook. He

fires the hook with an initial velocity of 85 m/s at an angle of 45o
with respect to the
horizontal. How far from the base of the cliff (d) does the hook land?

1 answer

Vo = 85m/s[45o].
Xo = 85*cos45 = 60.1 m/s.
Yo = 85*sin45 = 60.1 m/s.

Tr = (Y-Yo)/g = (o-60.1)/-9.8 = 6.1 s.
= Rise time.

h = Yo*t + 0.5g*t^2
h = 60.1*6.1 - 4.9*(6.1)^2 = 184.3 m.

d = Yo*t + 0.5g*t^2=184.3 + 120=304.3m
0 + 4.9t^2 = 304.3
t^2 = 62.1
Tf = 7.9 s. = Fall time.

d =Xo * (Tr + Tf)
d = 60.1*(6.1+7.9) = 841.4 m.


91,75s = 105 m.